I noticed that we have a tag for transitive-closure, which seems to me as somewhat redundant. Here are two arguments I have in mind.
Firstly, it's unclear if we are talking about the general relational term, or just the specific set theoretic construction of a transitive set containing a given set.
Secondly, in the former (and likely) case, this should be just subsumed under relations, rather than existing on its own. There's little to no specialization in this tag that would require it to be separate.
Should this tag be removed? become a synonym of one of the relation-related tags? or perhaps I'm wrong, and there is a case for it being left on the site?